1. Technical Field
The present invention relates to a signal transmitting device for transmitting video signals of red, green and blue (R, G and B) according to DVI standard and other signals through an optical fiber, a transmitter and a receiver.
2. Related Art
In a signal transmitting device for transmitting a video signal from a source apparatus such as a personal computer (PC) or a DVD player to a display device, when the number of display pixels is increased with an enhancement in a definition of the display device, a high transfer rate is required correspondingly. In the case in which a signal is subjected to a long distance transmission, particularly, a transmission loss is great in an electric signal through an electric wire. For this reason, there is a possibility that a video cannot be accurately displayed on the display device. A waveform distortion is increased in an analog video signal so that quality of the video is remarkably deteriorated. Also in a digital video signal, moreover, quality of a signal is deteriorated through an electric cable according to Digital Visual Interface (DVI) standard. For example, referring to UXGA (1600×1200 pixels), a transmittable distance is restricted to be a short distance of approximately 10 m.
As a signal to be transmitted according to DVI standard, DDC (Display Data Channel)-Data (DDC data), DDC-Clock (DDC clock) and HotPlugDetect and +5V Power for a data communication of the display device are defined in addition to four signals including R, G and B video signals and a clock signal thereof. Furthermore, a control signal or an audio signal is also transmitted as a transmitting signal between the source apparatus and the display device if necessary. Video associated signals of R, G and B and the clock in the transmitting signals are high frequency signals. On the other hand, the control signal and the audio signal are lower frequency signals as compared with the video associated signals.